THE ll.ni: \ (il M.l.i; \-K \. 



£. SPHAEROZOSJtlA Corda. Alman. de Carlsb. i 



Cells united by a narrow Isthmus or by glandular processes, deeply Incised, 



bilobed; zygospore smooth, globose or oval. 

 Etymology: Greek a<j>a <a, sphere, and a, girdle. 



Sphaerozosma Kliforme (Ehrb.) Rabh. Elor. Eur. A.lg. III.. 149. IS 



Tessararthra filiformis Ehrb. Inf. 1836. 



Filament long, firm, enclosed in a mucous matrix; cells aboul as long 



constricted In the middle with a deep Incision; ends of lobes connected 



by two sessile glands; diameter of cells 12 19^ 

 Minden. PI. VI., Fig. 3. 



Sphaerozosma serratum Bail. Micr. Obs. in Smithson. Contrib. 1850, p. 37. 

 Cells deeply and acutely lobed, firmly united, both lobes with oonnivenl 



spines; cells joined by 2 short process.-,: gelatinous sheath broad; di 



ameter, 22-33 //, including spines. 

 Minden. PI. VI, Fig. 4. 



Sub-family IL— Didymoideae.— Cells after division all distinct 



SYNOPSIS. 



Cells fusiform or cylindrical, not constricted in the middle (in ours). 



Cells straight, chlorophyll in a parietal spiral Spirota* nia 



Cells curved or falcate, chlorophyll in parietal laminae Cloak Hum 



Cells straight, chlorophyll in distinct longitudinal bands Penium 



Cells oblong, or cylindrical, constricted in the middle. 



Chloroplasts axillary Docidiu m 



Chloroplasts parietal /'/. urotm nium 



Cells globose or short-oblong, deeply constricted. 



Half-cells or segments broader thau long, spinose Xanthidium 



Segments broader than long, not spinose, chloroplasts longitudinal parietal, 



Pleurotcu niopais 



Segments not spinose, chloroplasts radiate ( 'oamarium 



Segments with a single spine on each side, chloroplasts axillary Irthrodeamua 



Segments emargiuate, or incised at the ends, sinuate or lobed at the sides, 



— trum 



Segments 3-5 lobed, the lobes emarginate, sinuate, or incise I Wcraatet ioa 



Segments 3-mauy angled, or lobed, the angles generally acute or pro luced Into 

 awns Stauruatrum 



3. SPIROTAMNIA Bbeb. in Halls Brit. Desm. IT-. 1843. 



Cells straight, oblong, cylindrical, or fusiform, nol constricted in the middle, 

 both ends rounded or acuminate; chlorophyll arranged hi a parietal, spiral, 



left hand coiled band; propagal ion by cell dh ision 



Etymology: Creek n-nnn, ci.il, .- 1 u < I . fillet, 



Spiroi.-u'ii i.i condensata Breb. I. c. 



Cells cylindrical, straight. <>r slightly curved, l- 25 broad, s >>r l" times as 

 long; both ends rounded; spbral bands miking 8 12 turn-. 

 orbicular, areolate. I'l VI.. Pig. 2, 2 a, resting spore. 



